1. Abram, D. (1996). The spell of the sensuous: Perception and language in a more-than-human world. New York: Vintage Books.
2. Abram, D. (2010). The discourse of the birds. Biosemiotics 3(3): 263–275. Excerpt from D. Abram (2010): Becoming animal: An earthly cosmology. New York: Pantheon.
3. Brentari, C. (2015). Jakob Von Uexküll: The discovery of the Umwelt between biosemiotics and theoretical biology (Biosemiotics 9). Springer.
4. Buchanan, B. (2008). Onto-ethologies: The animal environments of Uexküll, Heidegger, Merleau-Ponty, and Deleuze. Albany: SUNY Press.
5. Deely, J. (2014). Semiotic entanglement: the concepts of environment, Umwelt, and Lebenswelt in semiotic perspective. Semiotica, 199, 7–42.